Steam-heating system



Nov. 5, 1929. E. w. LARSEN STEAM HEATING SYSTEM Filed April 12 1926 3 Sheets-Sheet 1 jkve/zZir cal/u 7V" M FM Nov. 5, 1929. E. w. LARSEN 1,734,334

STEAM HEATING SYSTEM Filed April 12 1926 3 Sheets-Sheet 2 Z Z6 Z4 l6 @2 21 5 I fave/2757 Nov. 5, 1929. E. w. LARSEN STEAM HEATING SYSTEM Filed April 12. 1926 3 Sheets-Sheet 3 I or glaces to be heated.

Patented Nov. 5, 1929 UNITED STATES PATENT. OFFICE STEAM-HEATING SYSTEM Application filed April 12,

The invention relates to heating systems and more particularly to that type in which steam is generated and conducted to a place ne object of the invention is to provide an improved heating system, in which the highest possible economy in fuel consumption and thermal efficiency are attained.

Another object of the invention is to pro: vide an improved steam heating system in which the products of combustion are commingled with the steam, so that substantially all of the heat units in the fuel will be utilized, and so that providing a stack or chimney for carrying off the waste products will be rendered unnecessary.

Other objects of the invention will appear from the specification.

The invention consists in the several novel features hereinafter set forth and more particularly defined by claims at the conclusion hereof.

In the drawings: Fig. 1 is a view, illustrating the heating system embodying one form of the inventlon. Fig. 2 is a longitudinal section of the device for generating the heating apparatus. Fig. 3 is a diagrammatic illustration of the eletrical circuit and devices for controlling the system. Fig. 4 is a view, illustrating a modified form of the invention, in which a radiating coil is used in an air distributing duct.

The invention is exemplified in a heating system comprising an apparatus or structure which is adapted to be placed in the basement or any other convenient place and is operative to generate a heating medium consisting essentially of steam. This structure comprises a frame 9 on which the generator proper is mounted.

The generator comprises a base 10 which is bolted to the top of one side of the frame 9, and is provided with an annular upwardly extending flange 11 forming a socket 12, in which the lower end of a retort or firebox 13 is hold. This retort is preferably formed of refractory and porous material, such as fire clay, is provided at its lower end with a central upwardly flared fuel and air 50 inlet 14, and has its side wall 13 flared up- 1926. Serial No. 101,243.

wardly to form a combustion chamber 15. The top of the retort is formed by a hemispherical or concavo-convex dome 16, which also is formed of fire-clay. This dome has its annular margin 17 substantially coincident to the upper rim or margin 18 of the wall 13 of retort 13. The'faces of the contiguous margins 17 and 18 are separated slightly by lugs 19 formed on the dome 16, to form a plurality of narrow slits or openings, through which the products of combustion will escape into a steam generating chamber 20 which surrounds the sides of, and extends over, the top of the retort. Chamber 20 is formed in a dome-like casing 21 which has its lower end fixedly secured to the base 10 and frame 9, and its annular side wall 21 and its curved top 21 are spaced so as to form a generating chamber of the desired capacity. This chamber is substan- 7o tially filled with carborundum crystals or other heat resisting pieces to distribute the water over a very extensive superficial heated area, and so the products of combustion will mingle with the water to generate steam, WltllOllt'lOSS of heat units in the conversion, but with a drop in temperature.

A water inlet duct 22 leads into the top 21 of chamber 20 which top conforms in curvature approximately to the dome 16 of the re 30 tort. A screen 23 is provided at the inner end of duct 22 to distribute the water delivered to the body of crystals 27 radially and evenly over the dome 16. The supply of water through duct 22 to the generating chamber is 35 controlled by a valve 24 which is suitably mounted in the casing 21 to control delivery of water from a supply pipe 25. A screw-plug 26 is provided at the upper end of the chamber which contains valve 24 to provide access to the valve when desired.

The body of crystals 27 in the generating chamber is supported by a screen or foraminous sheet 28 which extends between flange 11 of the base 10 and the margin of said base. The steam generated in chamber 20 passes out of said chamber throu h screen 28 into an annular outlet or cham er 29 formed in the base 10. A pipe 30 is connected to chamber 29 to deliver the steam to the desired point of 10 consumption. To automatically prevent the Water rom being fed into the generating chamber through duct 22 until the temperature in the generating chamber has been suflicientl raised to produce steam, a thermostatic ellows 31, operatively connected to a rod 33, is disposed in a duct 32 which leads from steam outlet 29 to pipe 30. The upper end of said rod is separate from, and adapted to lift, valve 24, which has its stem connected to a bellows 34, so that the rod will not be subjected to the pressure of the water. Bellows 31, when it becomes heated, will automatically expand so as to lift rod 33 and open the valve 24.

A duct 36 leads from one side of the base 10 to the inlet 14 of the retort. The gas or gaseous fuel is forced through duct 36 into the combustion chamber 15, where it is ignited, and heats the retort wall. The products of combustion escape from the combustion chamber through the slits bet-ween the dome 16 and the rim of the retort body 13, into the generating chamber containing the crystals. As a result, there is no waste of fuel. By properly proportioning air with the fuel, complete combustion, without heat losses, will result. The combustion in the chamber 15, not only keeps the part surrounding the wall at a high degree of heat, but the products discharging under pressure from the combustion chamber through the slits into the generating chamber strike the water coming down over the dome 16, tending to atomize it and spread it outward around the crystals and to turn it into steam in its downward path. If the retort be made of porous material, such as fire-clay, part of the water will be absorbed by it and be converted into steam on the inner or combustion side and pass out through the slits. Inasmuch as the products of combustion are commingled with the steam to conserve all the heat units, no separate outlet for the products is necessary.

A spark plug 39 has its sparking point disposed in the lower end of the retort 13 to ignite the fuel entering the chamber 15. This spark plug exemplifies ignition means for the fuel and is connected to a transformer which is mounted in a suitable housing 40, it being understood however, that any suitable ignition means may be used.

A rotary pump, comprising a vaned rotor 41, is connected to receive the gaseous fuel from a pipe 42 under control of a check-valve 43 (not shown) which opens only by the suction of said pump. A similar pump rotor 44 is connected to receive air from a pipe 45 and to discharge it into a pipe 46, into which the gas under pressure is also discharged, so that a combustible fuel of mixed air and gas will be forced under pressure into the inlet duct36. Both of the pump rotors are contained in a unitary casing 48 with independent chambers. Both rotors are mounted on a common shaft which is driven by an electric motor 58 through suitable reducing gearing (not shown). The motor is mounted on the frame 9 adjacent the casing 48.

In operation, the pumps 41 and 44 will force fuel, such as gas and air under pressure, into the combustion chamber 15. The air and gas are properly proportioned, for efiicient and substantially complete combustion of the fuel. In the combustion chamber, the fuel will ignite and heat the retort walls to a very high temperature, and the products of combustion will be delivered directly into the chamber 20 containing the crystals over which the feed-Water will be finely spread, so that it will be quickly converted into steam. The carborundum crystals will be thoroughly heated, both from the walls of the retort and directly from the products. The steam, generated in the crystal-filled chamber, will pass through screen 28 to the pipe 30 which will deliver the steam to the point Where it is to be consumed for heating. The thermostatic bellows 31 will automatically control the inlet of the feed-water, so that no water will pass into the generating chamber until it and the crystals therein have been sufficiently heated to flash the water into steam. In practice,'an insulating jacket, not shown, is usually placed around the casing 21 as well understood in the art.

In the form of the invention illustrated in Fig. 1, the pipe 30 of the generator is connected by a pipe 50 and branch pipes 51 to deliver the steam into radiators 52. The feed-water pipe 25 is connected to receive water from an elevated or pressure tank 53. The condensate from the radiators 52 is delivered through pipes 54 into the tank 53. Tank 53 receives water from any suitable source, such for example as a valve controlled supply pipe 56. A pipe 55 is adapted to conduct any excess of water in tank 53 to a drain. The uncondensed gases in the condensate are exhausted through a pipe 57 which leads to the outside, so that such gases will be eliminated from the water before it is returned to the generator.

A characteristic of the system is that the products of combustion, which pass from the combustion chamber 15 into the generating chamber for thermal efficiency, are mixed with the steam and delivered to the radiators from the generator. The steam is condensed in the radiators and the condensate is returned to the feed-water supply tank.

The invention thus exemplifies a heating system in which steam is generated and the products of combustion are commingled with the steam, so that all of the heat units are utilized. This renders a stack for carrying off the waste products unnecessary and avoids the heat losses which usually result in ordinary boiler practice.

It is contemplated that the system be automatically controlled and for this purpgse the, motor 58, for driving the air and fuel pumps, is connected to a line circuit comprising conductors 59 and 60. A switch 70 is included in the conductor 59 and is normally held in its open position by-a spring 71. A stepdown transformer for the controlling circuit comprises a helix 72 bridged between the conductors 59 and 60 and a helix 73 in the controlling circuit. A room thermostat 74 is connected by conductor 75 to one end of the helix 73 and the helices 7 6 of an electromagnet are included in said conductor. This magnet is adapted to operate the switch 70 to hold it closed and cause the motor 58 to operate the pumps while the contacts of the thermostatic switch 77 are closed, which occurs when heat is desired in the room which is to be heated. A conductor 78, between the other end of helix 73 and one of the contacts of switch 77, includes a switch 79 and a switch 80. Switch 80 is adapted to be opened and closed by a thermostat 81 which is connected to be thermally responsive to the temperature in the steam outlet pipe 30. This thermostat is connected to open the controlling circuit at switch 80 when the temperature becomes excessive. A thermostat 82 in the condensate return pipe 54 is connected to operate the switch 79 to open it and break the controller circuit in event that the steam in is transit through the radiator is not fully condensed. As a result, the motor circuit for forcing air and fuel into the retort will be stopped by release of the switch 70 when the controller circuit 75, 78 'is interrupted by the switch 77 which is controlled by the room thermostat, or when the temperature in the I pipe 30 becomes excessive, or when the condensate returning to the pressure tank 53 becomes hot. The spark plug 39 is operated by a step-up transformer comprising a helix 39 connected to the line-conductors 59 and 60 and a helix 39" connected to the spark plug and to a ground connection on the frame.

The invention thus exemplifies an automatic control for a steam heatin system, in

which the motor for forcing air and fuel under pressure into the retort of the generator is automatically stopped when the temperature of the steam or condensate becomes excessive, as well as responsively to a room thermostat.

In Fig. 4, the invention is illustrated in connection with a hot air system, in which the air is heated by a steam coil or radiator. In this form of the invention, the steam pipe 50 is connected to a coil of pi e 52 which serves to heat the air passing t rough the casing 86. Return pipe 54 from coil 52 discharges into the pressure tank 53. Air is admitted to the casing 86 through a duct 87 under control of a valve 88, and the casing 86 is connected by air flues 89 to registers 90 in the floor of the rooms to be heated. In this form of the invention, the heat is transferred from the steam coil orradiator to the hot air ducts, which deliver the air into the rooms to be heated. The generator used in this hot air system is automatically controlled by thermostats 74, 81 and 82 which are similar in function and construction to thermostats 74, 81 and 82 respectively.

The invention is not to be understood as restricted to the details set forth, since these may be modified within the scope of the appended claims, without departing from the spirit and scope of the invention.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a heating system, thecombination of a substantially closed combustion chamber, means for forcing air and fuel under pressure into the combustion chamber, a steam products of combustion from the combustion chamber to the generating chamber, a radiator, means for delivering steam and said products from the generating chamber to the radiator, means for returning the condensate from the radiator to the generating chamber, and means for automatically controlling the forcing means to render it inoperatlve when the temperature of the condensate from the radiator reaches a predetermined degree.

2. In a heating system, the combination of a substantially closed combustion chamber, means for forcing air and fuel under pressure into the combustion chamber, a steam generating chamber, means for delivering the products of combustion from the combustion chamber to the generating chamber, a radiator, means for delivering steam and said products from the generating chamber to the radiator, means for returning the condensate from the radiator to the generating chamber, means for automatically controlling the operation of the forcing *means in response to variations in the temperature in the means for returning the condensate, and means for automatically controlling the operation of said forcing means in response to changes in temperature in the steam delivery means.

3. In a heating system, the combination of a substantially closed combustion chamber, means for forcing air and fuel under pressure into the combustion chamber, a steam generating chamber, a tank connected to deliver feedwater to the generating chamber, means for delivering the products ofcombustion from the combustion chamber 'to the generating chamber, a radiator, means for delivering steam and said products'from the generating chamber into the radiator, a pipe for delivering condensate from the radiator to the tank, and means connected to said pipe to el iminate the uncondensed gases from the condensate before it is returned to the tank.

, 85 generating chamber, means for deliverlng the I 4. In a heating s stem, the combination of a combustion cham r, means for forcing air and fuel under pressure into the combustion chamber, a steam generating chamber heated by the products of combustion produced in the combustion chamber, a radiator, a pipe connection for delivering steam from the generating chamber and said products of combustion to the radiator, means forming an outlet whereby the steam condensate and the products of combustion are exhausted from the radiator, and means for automatically controlling the operation of the forcing means in response to changes in the temperature of the space around said radiator.

5. In a heating s stem, the combination of a combustion chamber, means for forcing air and fuel under pressure into the combustion chamber, a steam generating chamber heated by the products of combustion produced in the combustion chamber, a radiator, a pipe connection for delivering steam from the generating chamber and said products of combustion to'the radiator, means forming an outlet whereby the steam condensate and the products of combustion are exhausted from the radiator, and means for automatically controlling the air and fuel forcing means to render the same inoperative when the temperature in said pipe connection reaches a predetermined degree.

6. In a heating system, the combination of a combustion chamber, means for forcing air and fuel under pressure into the combustion chamber, a steam generating chamber heated b the products of combustion produced in the combustion chamber, a radiator, a pipe connection for delivering steam from the generating chamber and said products of combustion to the radiator, means forming an outlet whereby the steam condensate and products of combustion are exhausted from the radiator, and means for controlling the air and fuel forcing means in response to variations in the temperature of the condensate from the radiator.

7. In a heating system, the combination of a combustion chamber, means for forcing air and fuel under pressure into thecombustion chamber, a steam generating chamber heated by the products of combustion produced in the combustion chamber, a radiator, a pipe connection for delivering steam from the. generating chamber and said products of combustion to the radiator, means forming an outlet whereby the steam condensate and the products of combustion are exhausted from the radiator, a discharge pipe for the condensate connected to the outlet forming means, and means for automatically controlling the air-and fuel forcing means to render the same inoperative when the temperature in the discharge pipe reaches a predetermined degree.

8. In a heating system, the combination ofi a substantially closed combustion chamber, means for forcing air and fuel under pressure into the combustion chamber, a steam generating chamber, means for delivering the products of combustion from the combustion chamber to the generating chamber, a radiator connected to receive steam and said products from the generating chamber, means forming an outlet whereby the products of combustion and the condensate are exhausted from the radiator, and means for automatically controlling the operation of the forcing means responsively. to changes in the temperature produced by the radiator.

9. In a heating system, the combination of a substantiall closed combustion chamber, means for orcing air and fuel under pressure into the combustion chamber, a steam generating chamber, means for delivering the products of combustion from the combustion chamber to the generating.

chamber, a radiator, a pipe for .delivering steam and said products from the generating chamber to the radiator, means forming an outlet whereb the products of combustion and the con ensate are exhausted from the radiator, and means for automatically controlling the forcing means to render it inoperative when the temperature in the pipe between the generating chamber and the radiator reaches 'a predetermined degree.

10. In a heating system, the combination of a substantially closed combustion chamber, means for forcing air and fuel under pressure into the combustion chamber, a-

steam generating chamber, means for delivering the products of combustion from the combustion chamber to the generating chamber, a radiator, a pipe for delivering steam and said products from the combustion chamber to the radiator, means forming an outlet whereby the products ofcombustion and the condensate are exhausted from the radiator, mea,ns for automatically controlling the operation of the forcing means in response to changes intemperature in the pipe between the generating chamber and the radiator, and means for automatically controlling the operation of said forcing means in response to variations in the temperature of the space around the radiator.

11. In a heating system, the combination ,of a substantially closed combustion chamber, means for delivering fuel to said cham- 12. In a heating system, the combination of a substantially closed combustion chamber, means for delivering fuel to said chamber, a steam generating chamber, means for delivering the products of combustion from the combustion chamber to the generating chamber, a radiator, a pipe extending between the generating chamber and said radiator, means forming an outlet for the radiator, and a compressor for injecting air under pressure into the combustion chamber to facilitate combustion and to fdrce the said products into the generating chamber and then through the pipe to the radiator.

Signed at Chicago, Illinois, this 27th day of March, 1926.

EINER W. LARSEN. 

